Devices are known for providing at least one of a sense of force and a sense of touch to a hand or a finger of a user, including a device having an operation element attached to an external member to provide an external force to the hand or finger of the user. For example, there is known a robot device to be disposed on a desk or the like, including an element to be grasped by a user (an operation element), via which a sense of force or a sense of touch is provided to the user (JP-A-2007-510232), and a device in which wires are provided to extend from a hand or a finger of a user to surrounding, fixedly-located drive sources, so that a sense of force is generated by adjustment of tension of the wires (JP-A-2003-172662).
Further, as a device in which an operation element is not attached to an external member, there is a device that generates an external force in a desired direction by changing angular rotation speeds of multiple gyro motors (JP-A-2004-177360). In addition, there is proposed a pen-like operation element equipped with markers and built-in motors to generate a force in accordance with a position of the pen detected by a camera, whereby a user holding the pen can experience a sensation of touching an image (Sho Kamuro, Kouta Minamizawa, Naoki Kawakami, and Susumu Tachi: “Pen de Touch,” International Conference on Computer Graphics and Interactive Techniques archive SIGGRAPH '09, Posters, 2009). Further, there is proposed a device in which two motors and a belt are attached to a finger, so that control of a direction of rotation of each motor represents a force in a direction of pressing of the finger (vertical force) and a force moving the finger sideways (shearing force), thereby to allow a user to sense a weight or an inertial mass of an object (Kouta Minamizawa, Souichiro Fukamachi, Hiroyuki Kajimoto, Naoki Kawakami, and Susumu Tachi: “Wearable Haptic Display to Present Mass and Internal Dynamics of Virtual Objects,” Transactions of the Virtual Reality Society of Japan, Vol. 13, No. 1, 2008-03).
As described above, various techniques for providing a sense of force or a tactile sensation to a user in accordance with input operations have been proposed. Particularly, application of such techniques to a field of virtual reality or the like to provide a user with a sensation that emulates actual physical contact with an image displayed on a display unit is expected.